Torsional magnetic reconnection: The effects of localizing the non-ideal (ηJ) term

Wyper, P.; Jain, R.

Abstract

Magnetic reconnection in three dimensions (3D) is a natural extension from X-point reconnection in two dimensions. Of central importance in the 3D process is a localized non-ideal region within which the plasma and magnetic field decouple allowing for field line connectivity change. In practice, localized current structures provide this localization; however, mathematically a similar effect can be achieved with the localization of plasma resistivity instead. Physically though, such approaches are unrealistic, as anomalous resistivity requires very localized currents. Therefore, we wish to know how much information is lost in localizing η instead of current? In this work we develop kinematic models for torsional spine and fan reconnection using both localized η and localized current and compare the non-ideal flows predicted by each. We find that the flow characteristics are dictated almost exclusively by the form taken for the current profile with η acting only to scale the flow. We do, however, note that the reconnection mechanism is the same in each case. Therefore, from an understanding point of view, localized η models are still important first steps into exploring the role of non-ideal effects.

• Journal Article Type: Article
• Online Publication Date: Jun 13, 2011
• Publication Date: 2011-12
• Deposit Date: Oct 18, 2016
• Journal: Journal of Plasma Physics
• Print ISSN: 0022-3778
• Electronic ISSN: 1469-7807
• Publisher: Cambridge University Press
• Peer Reviewed: Peer Reviewed
• Volume: 77
• Issue: 06
• Pages: 843-855
• DOI: https://doi.org/10.1017/s0022377811000262
• Public URL: https://durham-repository.worktribe.com/output/1395192